docs: def is_choked_turbulent_l(dP, P1, Psat, FF, FL=None, FLP=None, FP=None):
      r'''Calculates if a liquid flow in IEC 60534 calculations is critical or
      not, for use in IEC 60534 liquid valve sizing calculations.
      Either FL may be provided or FLP and FP, depending on the calculation
      process.
  
      .. math::
          \Delta P > F_L^2(P_1 - F_F P_{sat})
  
      .. math::
          \Delta P >= \left(\frac{F_{LP}}{F_P}\right)^2(P_1 - F_F P_{sat})
  
      Parameters
      ----------
      dP : float
          Differential pressure across the valve, with reducer/expanders [Pa]
      P1 : float
          Pressure of the fluid before the valve and reducers/expanders [Pa]
      Psat : float
          Saturation pressure of the fluid at inlet temperature [Pa]
      FF : float
          Liquid critical pressure ratio factor [-]
      FL : float, optional
          Liquid pressure recovery factor of a control valve without attached fittings [-]
      FLP : float, optional
          Combined liquid pressure recovery factor with piping geometry factor,
          for a control valve with attached fittings [-]
      FP : float, optional
          Piping geometry factor [-]
  
      Returns
      -------
      choked : bool
          Whether or not the flow is choked [-]
  
      Examples
      --------
      >>> is_choked_turbulent_l(460.0, 680.0, 70.1, 0.94, 0.9)
      False
      >>> is_choked_turbulent_l(460.0, 680.0, 70.1, 0.94, 0.6)
      True
  
      References
      ----------
      .. [1] IEC 60534-2-1 / ISA-75.01.01-2007
      '''
      if FLP and FP:
          return dP >= (FLP/FP)**2*(P1-FF*Psat)
      elif FL:
          return dP >= FL**2*(P1-FF*Psat)
      else:
          raise Exception('Either (FLP and FP) or FL is needed')